This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This project will utilize arterial spin labeled (ASL) perfusion MRI to measure blood flow in the muscles of the arm, leg and foot in patients with peripheral vascular disease (PVD). The goal was to optimize and validate ASL as a diagnostic tool for PVD.